A complex system such as an aircraft may be generally composed of a number of systems, and enable functionality greater than their individual systems. Technological advances in many complex systems including aircraft and others such as those in the aerospace, automotive, marine, medical and electronics industries have led to numerous mutually-dependent systems, at least some of which may be designed by different teams from different companies in different geographical locations. Failures or malfunctions of one or more of these systems often affect other systems, directly or indirectly, the collection of these effects often referred to as “cascading” effects. Additionally, analysis of these system failures/malfunctions and their cascading effects at the complex-system level is often required as part of a certification process. Typically such analyses are manually performed by groups of system analysts, without reference to a process capable of facilitating such analyses. As complex systems and the systems of which they are composed become more integrated, traditional analysis methods may no longer be practical in terms of breadth of coverage and labor costs involved.
In the aerospace industry, for example, aircraft manufacturers assess the cumulative effects of safety-critical system failures to ensure that equipment operates as intended under all expected operating conditions. Standards established by regulators, such as Code of Federal Regulations (14 CFR) 25.1309, require that the hazard categorization of a failure takes into account all relevant factors. These factors may include effects on the vehicle (lost or degraded function/performance, reduction of safety margin), effects on crew members (increase in workload, adverse operational or environmental conditions), and/or effects on occupants.
There are a number of safety analysis practices in the aerospace industry. For example, functional hazard assessment (FHA) is a top-down analysis of functions to identify and classify the severity of failures of the functions. Fault tree analysis (FTA) is top-down analysis in which the causes of a failure effect are analyzed using logic (e.g., Boolean logic) that combines contributing failures. Failure modes and effects analysis (FMEA) is a bottom-up analysis approach to identify the effects of failures on system functions and operations. FMEA is often used in conjunction with FTA, and can serve to complete and validate the FTA. Model-based safety analysis (MBSA) is an emerging practice in which the system design and safety assessment processes develop a common model that is used to automatically generate a consistent set of safety artifacts, including minimal cut set (MCS) fault trees and FMEA summaries.
Therefore, it may be desirable to have a system and method that improves upon existing practices.